Biblical quotations quite rightly arouse suspicion. The Bible is hardly science- or evidence-based. Invariably biblical quotes are used by people who want to persuade you of some obviously asinine, apocalyptical or illogical proposition.
But, on this isolated occasion, I cannot resist Matthew’s words: “With what measure ye mete, it shallbe measured to you.”
And, yes, I am going to use the quote in reference to an apocalypse – a lifting of the veil so we can all see the impending catastrophe.
You see, the measure with which we are mete-ing climate change is deceptive. It lulls us into complacency and therefore might result, as Ross Garnaut warns, in too little being done too late to save us from environmental and economic havoc.
Measurements are critical. Our perceptions are based on measurements. We imagine a tree measuring 300 feet to be taller than one measuring 100 metres, yet it is shorter.
The metric system is exquisite if you are brought up on it from childhood so it is hard-wired in your brain like a language learned in childhood. If not, you can lose and never regain concepts because the units of measurement have changed. Not many Australians over the age of 50 have much idea of the difference between a gas-guzzling or economical car is because the conversion of two measures – miles and gallons – into litres and kilometres is hard enough, but when the expression is further converted from relating to a constant volume of fuel (a gallon) to a constant of distance (100 kilometres) it is just too hard.
Even now, most over 50s know that 35 miles a gallon is pretty good, but would have no idea what that was in litres per 100 kilometres.
I suspect part of the nonchalance about climate change might be because of the way we measure it.
The much-bandied-about two or three degrees rise in global temperature does not sound much. People live affluent lives in Singapore – average daily maximum around 30 degrees – and in Stockholm – average daily maximum seven degrees, so why should we worry about two or three degrees.
But the measurement invites the belittlement of the danger. We should stop measuring climate projections in degrees Celsius. We should start using percentages.
The degree measurement is even worse in the United States which uses Fahrenheit to measure temperature. Typical mild days are in the low 70s. Sure, a Fahrenheit degree is slightly smaller than a Celsius one (five-ninths to be precise), so a global warming of two degrees Celsius is roughly three degrees Fahrenheit, so that sounds more, but the three-degree warming is seen by the average American as three degrees out of 70 or so. It is seen as a trifle. Small wonder polls suggest Americans as less concerned about global warming than Europeans.
Even in countries that measure temperature in Celsius, a two-degree warming does not seem much.
Measuring by percentages, on the other hand, might engender some much-needed urgency in climate policy. It has some scientific difficulty. Upon what do you base your percentage change?
As a crude measure you could start with the proposition that the average world temperature is about 15 degrees. If you add two degrees to that, it would be 13 per cent. Ouch. When you describe a world 13 per cent hotter than it is now, people would start to take notice. Two degrees they can ignore.
Of course, we have air temperature and sea temperatures to contend with. Raising the temperature of air takes less energy than raising the temperature of water. There are other measurement difficulties, but they should be met because the present measurement method results in too much complacency in the face of danger.
Let me illustrate the point with another example. The way we measure speed invites complacency in the face of significant danger. It is quite idiotic that speedometers in cars go to 240km/h, when the maximum speed limit in most of Australia is 110km/h an hour.
The speedometer should only go to about 140km/h. The trouble with present speedometers is they create misconceptions. The first misconception is that 110km/h is really only about half-way, whereas the perception you want to provide is that 110km/h is starting to push the limits.
The second misconception is that the difference between, say, 50km/h and 60km/h is quite small. It comprises a very small portion of the speedometer’s dial. But the difference in stopping distance and injury between the two speeds is large indeed.
Indeed, other than suicide, road crash is the most likely cause of non-disease death in Australia. Driving about is the most dangerous thing we do, yet we measure the speed of our driving (the main source of danger) in a way that invites complacency.
As it happens, it seems that Australians are ahead of policy makers on climate change and appear to be willing to sacrifice some economic growth to do something about it. Perhaps that is because media likes a dramatic story, so climate change gets greater coverage than more mundane dangers.
But that could be shrugged off when immediate costs are put against a distant future risk.
So we need to balance of risks and costs intelligently. In any balancing of risks and costs – car speed and time or cheap carbon now against expensive damage later — measurement of the thing posing the risk should be done in a realistic way, not in a way that enables it to be shrugged off.
Two degrees – no worries. Thirteen per cent – ouch.
Hull’s rising heat
Three citizens have become hot and bothered about Crispin Hull’s seemingly unremarkable assertion that a rise in average Earth temperature from 15 degrees to 17 amounts to (about) 13per cent (Letters, September 15). D. Zivkovic says that, in coming to this conclusion, Hull has committed a logical error that any Year 9 student would not make. God help the education system if he is right about that. There are no logical errors in Hull’s article. Contrary to Zivkovic’s misinterpretation, the article is all to do withgeneral misunderstandings about measurement scales and percentages derived therefrom. Aert Driessen says Hull should have gone on to assert that the 2 per cent increase in degrees Fahrenheit equates to ”an increase of atmospheric CO2 content from 0.00038 per cent to 0.0004 per cent (380ppm to 400ppm)”. He had the science wrong here: substitute 450/480 for 400. But his point is well made and, apparently unrecognised by him, is a good example of the thrust of Hull’s article. Annette Barbetti moves the goal posts right down into the nether world and starts the temperature scale at Kelvin’s absolute zero: whence the rise is 0.694 per cent. The irony is that all three, in criticising Hull, are victims of the errors he was concerned about.
Jack Lonergan, Isaacs
Degrees of ridicule
After Jack Lonergan ridiculed me and other letter writers for failing to get the point of Crispin Hull’s ”Two degrees of separating wheat from chaff on warming” (September 13, pB9), I re- read Hull’s article again several times, wondering if Lonergan was right and the rest of us so wrong. Nope, I still don’t know what Lonergan was going on about. I might be too thick to get what Hull meant to say, but I can read, and this is what he did say: ”We should stop measuring climate projections in degrees Celsius. We should start using percentages.” He implied, erroneously, that it made sense to measure temperature changes in percentage terms. By cherry-picking the Celsius scale because it makes global warming seem bad, and deriding the Fahrenheit scale simply because it makes it seem like a ”trifle”, Hull was guilty of intellectual dishonesty. Specious analogies with car speedometers didn’t help. His closing paragraph ”Two degrees. No worries. Thirteen per cent. Ouch” was a perfect way for him to conclude his article because it summed up indeed admitted that dishonesty. If my letter had been published in its entirety (minus the errors introduced by the sub-editor) it would perhaps
have been clear that I was mocking the notion that 13 per cent (Celsius) was any more meaningful than 6 per cent (Fahrenheit), or 1 per cent (Kelvin). There are legitimate ways of explaining to the public that two degrees of warming might really be something to worry about. Expressing it as a percentage of some arbitrary number is not one of them. D.Zivkovic, Aranda
I am delighted at Jack Lonergan’s response (Letters, September 17) to my letter of September 15 because it gives me the opportunity to talk science instead of politics. Lonergan believes that I should have factored in a CO2 increase as high as 480ppm instead of the 400ppm in my example. It really doesn’t matter, even if he wanted me to take it up to 1000ppm. He obviously thinks that the relationship between rising CO2 and warming is linear. But it is not. It is logarithmic. Warming caused by an increase of CO2 from, say, 10ppm to 20ppm (about 1.5 centigrade degrees, not 1.5 degrees C) is more than 10 times greater than the warming effect reflecting an increase of CO2 from 100ppm to 200ppm, and much greater still for warming caused by CO2 increases from say 500ppm to 1000ppm. By way of visualising this, if changes in temperature are plotted on a vertical axis (from zero to 1.6 C degrees) and CO2 concentration is plotted on a horizontal axis (from zero to 480ppm) then the graph line depicting the relationship between these two variables looks like a ski jump. It starts top left at 1.5 C degrees when CO2 concentration is 20ppm and drops very quickly to 0.2 C degrees when the CO2 content is about 80ppm. At 200ppm CO2 the line is practically horizontal, meaning that even very large increases in CO2 (running the line further to the right), even to 1000ppm, would hardly register on the vertical axis and so indicate only a negligible warming effect. Strange how nature works.
Aert Driessen, McKellar
Hull is not even right to a degree, let alone two of them
By The Canberra Times
Crispin Hull (Two degrees of separating wheat from chaff on warming, pB9, September 13) made a basic error of logic that a Year 9 science student should be able to spot. According to him, if we assume that the average world temperature is 15 degrees, then a warming of two degrees represents 13 per cent, which sounds like a lot. Ignoring the important question of whether ”average world temperature” is even a meaningful concept, the problem is that five degrees measured from an arbitrary zero point, the freezing point of water. The fact that Hull knew enough to ask the crucial question, ”Upon what do you base your percentage change?” made his article look like a propaganda piece rather than simple ignorance. The freezing point of water has no special cosmic significance. The Fahrenheit scale puts it at 32F, therefore a rise of 3.6F (2C) from 59F is 6 per cent, which doesn’t sound nearly as
bad as 13 per cent. Hull implied that the Fahrenheit scale is somehow ”worse” than Celsius (apparently only because it makes global warming seem smaller), but both are just arbitrary ways of measuring temperature. The bottom line is, 2 per cent, 6 per cent and 13 per cent are pretty meaningless: two degrees is two degrees.
D.Zivkovic, Aranda
20 parts per million
If Crispin Hull wants to further sensationalise global warming reporting by saying warming has increased 13 per cent instead of two degrees Celsius if average global temperature (whatever that means) rises from 15C to 17C, he should also say that what this fuss is all about is an increase of atmospheric CO2 content from 0.00038 per cent to 0.0004 per cent (380 ppm to 400 ppm).
Aert Driessen, Mackellar
Absolute zero marks
Crispin Hull thinks that a 2C increase in temperature would mean a 13 per cent hotter world. He is mistaken. He should have measured the temperature from absolute zero (zero degrees K, or minus 273.15 degrees C). The temperature would rise from 288.15K to 290.15K, or 0.694 per cent. Annette Barbetti, Kaleen
What’s your speed?
I believe Mark Wilson (Letters, January 7) does Robert Miles (Letters, January 5) an injustice in regards to speedometer readings, and myself on technologically controlled speed limitations (Letters, July 13), but does make some good points.
While Miles refers to a brilliant suggestion of a year or two ago, there have been recent letters too.
Crispin Hull made the key point about perceptions, using speedometer readings as one of several examples (Opinion, September 13, p9).
Several letter writers completely misunderstood Hull’s article, except perhaps Jack Lonergan (Letters, September 17) and myself (unpublished).
Speedos commonly read from 0 to 240-odd km/h. So, in Australia, you are certainly speeding when the needle is only halfway around the dial.
Hull’s idea was to change the dial to read, say 0-130km/h so that your perception of speeding would be more apparent when the needle was nearly fully wrapped clockwise around. Miles understood this, but used the 0-110km/h range as an example.
Wilson is up in arms on this, but Miles did say, for example, 110km/h. So make the top speedo number, say, 130km/h. This covers all of Wilson’s points, while not unduly compromising Hull’s original idea.
As for my suggestion on technologically imposed car speeds, 20km/h over seems reasonable.
Professor Greg Jackson, Kambah